title: Adolescent alcohol exposure alters the central brain circuits known to regulate the stress response.
abstract: Adolescent alcohol exposure (AAE) may exert long-term effects on the adult brain. Here, we tested the hypothesis that the brain regions affected include the rat hypothalamic-pituitary-adrenal (HPA) axis. Specifically, we examined the consequences of AAE [postnatal days (PND) 28-42] on the HPA axis-related brain circuitry of male rats challenged with an intragastric (ig) administration of alcohol in young adulthood (PND 61-62). Adolescent rats were exposed to alcohol vapors, while controls did not receive the drug. The mean blood alcohol level in adolescence on PND 40 was 212.8±5.7 mg %. Using immunohistochemistry and in situ hybridization procedures, we measured signals for c-fos and corticotropin releasing factor (CRF) in the paraventricular nucleus (PVN) of the hypothalamus, as well as signals for c-fos and phenylethanolamine N-methyltransferase (PNMT) in the adrenergic brain stem regions (C1 and C2). PVN CRF mRNA expression was significantly blunted in AAE rats tested at PND 61-62, compared to their controls. These animals also displayed a significant increase in the mean number of PNMT-ir cells/brain stem section in the C2 area. Collectively, these results suggest that exposure to alcohol vapors during adolescence exerts long-term effects on the ability of the PVN to mount a response to an acute alcohol administration in young adulthood, possibly mediated by medullary catecholamine input to the PVN.
authors.affiliation: The Salk Institute, The Clayton Foundation Laboratories for Peptide Biology, La Jolla, CA 92037, USA.
authors.forename: C D
authors.initials: CD
authors.lastname: Allen
authors.forename: C L
authors.initials: CL
authors.lastname: Rivier
authors.forename: S Y
authors.initials: SY
authors.lastname: Lee
mesh_terms: D000375:Aging / Q000502:physiology; D020268:Alcohol-Induced Disorders, Nervous System / Q000378:metabolism / Q000503:physiopathology*; D000818:Animals; D001933:Brain Stem / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology*; D004195:Disease Models, Animal; D000431:Ethanol / Q000097:blood / Q000506:poisoning; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects* / Q000503:physiopathology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013315:Stress, Psychological / Q000139:chemically induced / Q000503:physiopathology*
chemical_list: D000431:Ethanol